package com.example.springcloud.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * @ClassName MyLoadBalancer
 * @Author Admin
 * @Date 2020/9/4 6:29
 * @Version 1.0
 **/
@Component
public class MyLoadBalancer implements LoadBalancer {
    private AtomicInteger atomicInteger = new AtomicInteger(0);

    public final int getAndIncrement() {
        int current;
        int nex;
        do {
            current = this.atomicInteger.get();
            nex = current >= Integer.MAX_VALUE ? 0 : current + 1;

        } while (!this.atomicInteger.compareAndSet(current, nex));
        System.out.println("****第几次访问，次数nex:" + nex);
        return nex;
    }

    @Override
    public ServiceInstance instance(List<ServiceInstance> serviceInstances) {
        int index = getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }
}
